struphy 3.0.4

Multi-model plasma physics package

Welcome!

This is a Python package for solving partial differential equations (PDEs) mainly - but not exclusively - for plasma physics.

STRUPHY stands for STRUcture-Preserving HYbrid code (or STRUcture-preserving PHYsics code). The package provides off-the-shelf models for plasma physics problems, such as

• Maxwell's equations
• Magneto-hydrodynamics (MHD)
• Vlasov-Poisson and Vlasov-Maxwell kinetic models
• Drift-kinetic models for strongly magnetized plasma
• MHD-kinetic hybrid models

All models can be run on multiple cores through MPI (distributed memory) and OpenMP (shared memory). The compute-intensive parts of the code are translated and compiled ("transpiled") using pyccel, giving you the speed of Fortran or C while working within the familiar Python environment.

Particles in a Tokamak (model "Vlasov")	Toroidal Alfvén eigenmode (model "LinearMHDDriftKineticCC")
Strong Landau damping (model "VlasovAmpereOneSpecies")	Anisotropic diffusion (propagator "ImplicitDiffusion")

The code is freely available under an MIT license - Copyright (c) 2019-2026, Struphy developers, Max Planck Institute for Plasma Physics.

Tutorials

Get familiar with Struphy right away on mybinder - no installation needed.

Quick install

Quick install on your computer (using a virtual environment):

python -m venv struphy_env
source struphy_env/bin/activate
pip install -U pip
pip install -U struphy
struphy compile

In case you face troubles with install/compile:

1. check the prerequisites
2. visit trouble shooting

Docker

If you want to get started right away without installing anything, you can use the Docker image - just pull and run:

docker pull spossann/struphy:main
docker run -it --rm spossann/struphy:main
ls struphy_*

This will show three available Struphy environments, which you can activate for example via

source struphy_fortran_/env_fortran_/bin/activate

There is also a Docker image with just the prerequisites (on Ubuntu), so you can install and compile Struphy on top of it yourself:

docker pull spossann/ubuntu-for-struphy:main
docker run -it --rm spossann/ubuntu-for-struphy:main

Quick run

As an example, let's say we want to solve Maxwell's equations. We can use the CLI and generate a default launch file via

struphy params Maxwell

Hit yes when prompted - this will create the file params_Maxwell.py in your current working directory (cwd). You can open the file and - if you feel like it already - change some parameters, then run

python params_Maxwell.py

The default output is in sim_1/ in your cwd. You can change the output path via the class EnvironmentOptions in the parameter file.

Parallel simulations are run for example with

pip install -U mpi4py
mpirun -n 4 python params_Maxwell.py

You can also put the run command in a batch script.

Documentation

The doc is on Github pages, we recommend in particular to visit:

• Install
• Userguide
• Available models
• Numerical methods

Get in touch

• Issues
• Discussions
• @spossann [e-mail] (Maintainer)
• @max-models [e-mail] (Maintainer)
• LinkedIn profile

Citing Struphy

• S. Possanner, F. Holderied, Y. Li, B.-K. Na, D. Bell, S. Hadjout and Y. Güçlü, High-Order Structure-Preserving Algorithms for Plasma Hybrid Models, International Conference on Geometric Science of Information 2023, 263-271, Springer Nature Switzerland.